Chain tensioners (sometimes called “tie down tensioners”) are commonly used to secure cargo during transport. A chain tensioner will typically comprise an apparatus with a hook at one end and a means for attaching a chain at the other. The chain may be attached to the cargo, while the hook may be attached to a tie-down ring on an aircraft or other form of transport. After the chain is initially attached between the chain tensioner and the cargo, a tensioning wheel on the chain tensioner may be rotated to effectively reduce the length of the chain tensioner, and thereby increase the tension on the chain. Later, the chain may be quickly released by manipulating a release handle on one side of the chain tensioner. Such chain tensioners are available from, for example, Davis Aircraft Products Co. (Bohemia, N.Y., USA), as well as others.
When utilizing a chain tensioner to restrain cargo, it is generally preferred that the release handle face upward so that the operator can quickly ascertain its state and avoid unintended releases. In November 2011, the U.S. Department of Defense (DOD) reinforced this preference by publishing Detail Specification MIL-DTL-25949H, which is hereby incorporated by reference herein. In this Specification, the DOD requests a new chain tensioner design with the ability to rotate its hook relative to the remainder of the device. More specifically, the requested chain tensioner must have the capability of swiveling and locking the hook into two positions 180-degrees from one another. The Specification further requires that the hook shall be capable of rotating in both the clockwise and counterclockwise directions, and that no tools shall be required to rotate and lock the hook into the new orientations.
For the foregoing reasons, there is a need for new chain tensioner designs that incorporate hook connection assemblies capable of allowing a hook to be swiveled between, and locked into, multiple orientations.